The hunt for something better than Advertising Value Equivalency (AVE) has led some PROs down a road where ‘engagement’ has become the measurement of choice and digital the medium to achieve it. This is a metric which I’d like to quietly strangle in a cul-de-sac.

Digital and its social media sidekick have clearly fragmented traditional media. They have allowed us to identify and segment audiences. Online, digital marketing can target the people who have previously bought your product or identify new ones from their Google searches; messages can be tailored for different audiences. So far so good. But are page impressions, ‘likes’ and retweets meaningful hard data?

But where is the empirical evidence that consumers are moving away from companies with strong reputations and great products and services and embracing those who want to ‘engage’ digitally?

People enthusiastically engage with their friends on social media and share experiences, opinions and images. But in the main they refuse to talk with or about brands except to complain. As reported in the FT last year by a senior marketer at Diageo: "After 10 or 15 years of f***ing around with digital we’ve realised that people don’t want to ‘engage’ with brands, because they don’t care about them."

In 2013, Oslo advertising agency DIST Creative persuaded Burger King Norway to force its declared Facebook followers to choose one of two options: click "I am a true fan" and gain access to a new VIP Facebook page or click ‘I am a sellout’ and be banned from the new page for life and given a voucher for a free Big Mac. It was disastrous. According to Ad Age, 38,000 people took part in this campaign and only 8,000 chose to stick with BK. Moreover, BK only had 1000 Big Mac coupons to give away so 29,000 were cheated. Not only had BK Norway traded "likes" for customers and lost but to nail down 8,000 "more engaged" customers (whatever that achieves) they upset 29,000 people.

In 2010, Pepsi diverted much of its TV advertising budget into a social media campaign: the "Pepsi Refresh Project". Consumers were invited to propose ideas that would have a positive impact on society; Pepsi spent $20 million funding the ones that gained the most votes via various social media channels. It garnered over 80 million votes, 3.5 million ‘likes’ on the Pepsi Facebook page and about 60,000 new Twitter followers. It also failed to sell Pepsi; the company lost about 5 per cent of its market share over the course of the year, and Pepsi returned to TV advertising.

Clicking a ‘like’ button is not engagement; it requires no commitment. About seven in 10,000 of a major brand’s followers will engage with a Facebook post; for Twitter it’s about three in 10,000. I might ‘like’ a funny "Overheard in Waitrose" Facebook posting but it doesn’t stop me shopping at Sainsbury’s. There’s nothing wrong with Amazon clocking up five million Facebook likes in the USA and two million Twitter followers. But I bet most buy stuff from other places too.

Professor Byron Sharp notes that most of any successful brand’s sales come from infrequent ‘light buyers’ – millions of people who buy only occasionally and buy competing brands in between. So we need to recognise the limits to ‘engagement’. Light buyers aren’t fans of your brand. They don’t think of it as special or even unique. They won’t follow you on Twitter or visit your Facebook page. They can probably think of a hundred things they’d rather do than share a "digital experience".

And Amazon clearly still has a reputation problem with a number of its other audiences. The public may carry on buying despite their dislike of its tax arrangements but politicians and regulators are passing legislation to tax it more heavily. Has the number of people who ‘liked’ US restaurant company Chipotle’s "Food with Integrity" campaign and downloaded its game app helped them defend reputation during their recent E.coli crisis?

As PR moves into areas which were previously considered the domain of marketing and creative advertising, digital has become intrinsic to it. But PROs should not be relegating journalists to the status of ‘also-rans’. These people influence multiple audiences.

Many PROs have never seen the inside of a newsroom but print and broadcast media can reach millions of people with your point of view and convert people to it. Digital marketing strategies enjoy bypassing pesky journalists with their troublesome questions – but that is why a positive news report has more value than ‘likes’ on Facebook. Journalists remain the independent verifiers of your ‘truth’.

As the CIPR defines it, Public Relations is about reputation – the result of what you do, what you say and what others say about you. There’s a place for digital engagement – but let’s not confuse the metrics around it with the proper measurement, evaluation and insight to be derived from all parts of reputation management.